breast cancer pathology Flashcards
how has breast cancer rates changed over time
It has decreased in the last 20 years
breast cancer risk factors
Familial: BRCA1/BRCA2, Li Fraumeni syndrome (p53 mutation), Cowden syndrome (PTEN mutation), Peutz-Jeghers syndrome (STK11/LKB1 mutation). Sporadic: increasing age, young age at menarche, late menopause, hormonal, post-menopausal women, ionizing radiation, family history. Having a child earlier in life is protective
Functions of BRCA1 and 2, and cancers associated with them
•Both are tumor suppressor genes which facilitate DNA damage repair (loss of function progresses to cancer). BRCA1: breast cancer, ovarian cancer. BRCA2: breast cancer (males too), ovarian cancer
most common metastases to breast and who gets metastatic breast cancer
hematoogic, melanoma, lung, ovarian, kidney, prostate, stomach. • Curiously, in persons <20 yrs old metastatic lesions are more common than primary malignant lesions, but this is a very small subset of patients
Carcinoma in-situ
A general concept in neoplastic pathology where neoplastic epithelial cells grow within the confines of the basement membrane. The tumor has not yet become invasive
ductal carcinoma in situ histology
Clonal proliferation of epithelial cells within the ducts leaving the myoepithelial layer and basement membrane intact. Five classic histologic patterns include comedo (central necrosis), solid, cribriform (punched-out holes), papillary (large projections into the lumen) and micropapillary (small projections into the lumen)
DCIS presentation
calcifications seen on mammography. Generally asymptomatic and nonpalpable
DCIS grade
Comedo pattern contains central necrosis and is always high grade, other types range from low to high grade. 6. Low grades often express hormonal receptors (estrogen and progesterone), high grades often overexpress Her2/neu.
DCIS progression and risk of recurrence
DCIS is associated with a significant risk of developing invasive carcinoma. Risk factors for recurrence of DCIS include (1) histologic grade, (2) extent of breast involvement (size of DCIS), (3) if the DCIS is completely excised (if the margins are negative for DCIS)
DCIS treatment
Surgical excision (+/- other therapies) is curative in the vast majority of cases of tumors consisting purely of DCIS
Pagets disease
Neoplastic DCIS cells grow from the ducts onto the adjacent skin without invading through the basement membrane of the ducts or skin. Clinically presents as a scaly rash on the nipple. Many have associated invasive carcinoma including 1/3 who present without an associated mass and >9/10 of those with a mass. Prognosis depends on the presence of underlying carcinoma
Pagets histology
Paget cells= large cells in epidermis with clear halo
Lobular carcinoma in situ (LCIS)
- “Classic” LCIS always an incidental finding, does not form masses or calcifications. 2. Often multicentric and bilateral. 3. Patients are at a significantly increased risk for development of invasive carcinoma in both breasts (compared with DCIS were the higher risk is predominantly in the ipsalateral breast)
LCIS histology
small, uniform cells with round nuclei filling the lobules and poorly adhering to adjacent cells. 5. Some recognize a “pleomorphic” variant of LCIS that behaves more aggressively and some advocate treating these similar to DCIS
LCIS genetic alterations
The cells adhere to each other poorly because they have lost the function of important cell-cell adhesion molecules, chiefly e-cadherin.
Types of atypical hyperplasia
Technically not yet a carcinoma, but has some histologic features of in situ carcinoma. Can resemble DCIS, termed atypical ductal hyperplasia (ADH). Can resemble LCIS, termed atypical lobular hyperplasia (ALH). Both have increased risk of invasive carcinoma
Invasive carcinoma presentation
Commonly present as a palpable mass or as a mammographic abnormality. Uncommon presentations include an enlarged erythematous breast (termed “inflammatory carcinoma”) or as metastatic disease (typically an axillary lymph node). Advanced lesions fix the mass to the underlying chest wall and cause dimpling of the overlying skin.
Where does invasive carcinoma usually occur
Carcinoma most commonly occurs in the upper outer quadrant; these tumors spread first to axillary lymph nodes. When tumors occur in the inner quadrant they preferentially spread to the internal mammary lymph nodes
What causes inflammatory carcinoma
Diffuse involvement of dermal lymphatics (carries a poor prognosis)
invasive ductal carcinoma histology
Well-differentiated tumors contain well formed ducts with relatively bland appearing cells infiltrating a dense fibrous stroma. Poorly-differentiated tumors have either poorly formed ducts or no duct formation in which case they are composed of irregular groupings of markedly atypical appearing cells. Sheets, nests, cords or individual cells. DCIS alos occurs in up to 80%.